1. Field of the Invention
The present invention relates to a computer touch input device or other trace-detection input device such as an optical tracing plate or module, and in particular to a depressible mechanism for a trace detecting module that generates a control signal. The control signal thus generated is in addition to the trace detecting signal, so that the user can generate both trace-detection signals and control signals by moving a single finger or other object.
2. Description of the Prior Art
In order to replace a conventional mouse, a variety of touch pad devices (computer touch input devices) have been applied to a computer system, such as a notebook computer, for controlling cursor movement or scrolling a window-based application on a display.
U.S. Pat. Nos. 5,578,817, 5,623,553, 5,801,681, and 6,552,713 disclose trace-detecting devices in which, if an object moves across a tracing plate of the trace detecting device, the trace-detecting device will generate a trace-detecting signal to the computer in response to movement of the object relative to the trace detecting device.
However, if the user wishes to execute a program or a hyperlink on the display, the user still has to use other fingers to depress a corresponding button which is provided with conventional mouse control functions. This is a problem because most users use their index finger to control cursor movement and the thumb and middle finger to depress buttons, resulting in unnatural finger exercise that tends to cause fatigue of the user's hand.